Re: [PATCH] ext4: Fix return-value types in several function documentation comments

From: Ritesh Harjani
Date: Mon Mar 30 2020 - 00:17:40 EST




On 3/30/20 1:51 AM, Josh Triplett wrote:
The documentation comments for ext4_read_block_bitmap_nowait and
ext4_read_inode_bitmap describe them as returning NULL on error, but
they return an ERR_PTR on error; update the documentation to match.

The documentation comment for ext4_wait_block_bitmap describes it as
returning 1 on error, but it returns -errno on error; update the
documentation to match.

Signed-off-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx>

Thanks for your patch.
Reviewed-by: Ritesh Harani <riteshh@xxxxxxxxxxxxx>


Just a note for next time:-
"Update the documentation to match" - could be misleading.
As 'Documentation' is generally referred as info inside Documentation/
directory in kernel. We could just say as-
"Update the function comment description"


---
fs/ext4/balloc.c | 4 ++--
fs/ext4/ialloc.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 8fd0b3cdab4c..9a296008cf90 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -410,7 +410,7 @@ static int ext4_validate_block_bitmap(struct super_block *sb,
* Read the bitmap for a given block_group,and validate the
* bits for block/inode/inode tables are set in the bitmaps
*
- * Return buffer_head on success or NULL in case of failure.
+ * Return buffer_head on success or an ERR_PTR in case of failure.
*/
struct buffer_head *
ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
@@ -502,7 +502,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
return ERR_PTR(err);
}

-/* Returns 0 on success, 1 on error */
+/* Returns 0 on success, -errno on error */
int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
struct buffer_head *bh)
{
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index f95ee99091e4..86a96dca9ebf 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -113,7 +113,7 @@ static int ext4_validate_inode_bitmap(struct super_block *sb,
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
- * Return buffer_head of bitmap on success or NULL.
+ * Return buffer_head of bitmap on success, or an ERR_PTR on error.
*/
static struct buffer_head *
ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)